Ogawa Shouhei, Katoh Masahiko, Sato Takeshi
a Department of Civil Engineering, Graduate School of Engineering , Gifu University , 1-1 Yanagido, Gifu 501-1193 , Japan.
Environ Technol. 2015;36(20):2647-56. doi: 10.1080/09593330.2015.1042071. Epub 2015 May 15.
This study investigated whether a combined application of hydroxyapatite and ferrihydrite could immobilize lead and antimony in shooting range soil in which the level of lead contamination is markedly higher than that of antimony. In addition, we evaluated the stability of lead and antimony immobilized by the combined application with varying soil pH. The levels of water-soluble lead and antimony for the combined application were lower than those of single applications of hydroxyapatite or ferrihydrite, indicating that the combined application could suppress the levels of water-soluble lead and antimony by 99.9% and 95.5%, respectively, as compared with the levels in shooting range soil without immobilization material. The amounts of residual lead and amorphous Fe/Al oxide-bound antimony fractions in sequential extraction increased with a decrease in the exchangeable and carbonate lead fractions as well as in non-specifically bound and specifically bound antimony fractions. The alteration of lead and antimony phases to chemically more stable ones as a result of the combined application would result in the suppression of their mobility. The stability of immobilized lead and antimony in the combined application was equal to that of lead with a single application of hydroxyapatite and that of antimony with a single application of ferrihydrite within neutral to alkaline pH conditions, respectively. Therefore, this study suggests that the combined application of hydroxyapatite and ferrihydrite can simultaneously immobilize lead and antimony in shooting range soil with neutral to alkaline pH.
本研究调查了羟基磷灰石和水铁矿联合应用能否固定靶场土壤中的铅和锑，该靶场土壤中铅污染水平明显高于锑污染水平。此外，我们评估了在不同土壤pH值条件下，联合应用固定铅和锑的稳定性。联合应用时水溶性铅和锑的含量低于单独施用羟基磷灰石或水铁矿时的含量，这表明与未添加固定材料的靶场土壤相比，联合应用可分别将水溶性铅和锑的含量降低99.9%和95.5%。连续提取中残留铅和无定形铁/铝氧化物结合锑组分的含量随着可交换态和碳酸盐结合态铅组分以及非特异性结合态和特异性结合态锑组分的减少而增加。联合应用使铅和锑的相态转变为化学稳定性更高的相态，这将导致它们迁移性的降低。在中性至碱性pH条件下，联合应用中固定铅和锑的稳定性分别与单独施用羟基磷灰石时铅的稳定性以及单独施用 水铁矿时锑的稳定性相当。因此，本研究表明，羟基磷灰石和水铁矿联合应用可同时固定中性至碱性pH值靶场土壤中的铅和锑。
